Accession Number : ADA222272


Title :   High Resolution Electron Energy Loss Spectroscopy Studies of Chemisorbed Species on Metal Surfaces


Descriptive Note : Final rept. 1 Apr 1986-31 Oct 1989,


Corporate Author : TEXAS UNIV AT AUSTIN DEPT OF PHYSICS


Personal Author(s) : Erskine, J L


Full Text : http://www.dtic.mil/dtic/tr/fulltext/u2/a222272.pdf


Report Date : 31 Mar 1990


Pagination or Media Count : 15


Abstract : The objective of this research program is to utilize high resolution electron energy loss spectroscopy and other spectroscopic tools to investigate chemical and physical properties of surfaces and of gas-surface interactions. Our experiments address issues pertaining to bond lengths and site symmetry of chemisorbed atoms and molecules at metal surfaces, binding energies and vibrational frequencies associated with the atomic and molecular bonds, and with the driving mechanisms responsible for structural transformations which occur at surfaces as a result of chemisorption or other perturbations such as temperature change. Our work also addresses possible improvements in experimental techniques and data analysis which offer expanded applications. Research accomplishments of the program include a significant advancement in instrumentation, the first measurements of shear horizontal vibrational modes at crystal surfaces, the first detection of projected bulk phonon modes by surface electron scattering and elucidation of novel properties associated with hydrogen interaction at Niobium surfaces. (jg)


Descriptors :   *HIGH RESOLUTION , *CHEMISORPTION , *LOSSES , *ELECTRON ENERGY , *SURFACES , *SPECTROSCOPY , SCATTERING , SHEAR PROPERTIES , DETECTION , HORIZONTAL ORIENTATION , INTERACTIONS , TOOLS , CHEMICAL PROPERTIES , MOLECULES , PHYSICAL PROPERTIES , STRUCTURAL PROPERTIES , EXPERIMENTAL DESIGN , SITES , ELECTRON SCATTERING , CRYSTALS , ATOMS , PHYSICAL CHEMISTRY , HYDROGEN , PHONONS , CHEMICAL BONDS , ELECTRONS , GAS SURFACE INTERACTIONS , SURFACE PROPERTIES , NUCLEAR BINDING ENERGY , LENGTH , SYMMETRY , NIOBIUM , PERTURBATIONS , BONDING , TRANSFORMATIONS , EXPANSION , SURFACE CHEMISTRY , TEMPERATURE , METHODOLOGY , MEASUREMENT , DATA PROCESSING , FREQUENCY , VIBRATION


Subject Categories : Physical Chemistry
      Atomic and Molecular Physics and Spectroscopy


Distribution Statement : APPROVED FOR PUBLIC RELEASE